Marriott International Corp. was recently the victim of a rare type of targeted attack: A hacker pilfered sensitive documents from the hotel chain and then attempted to use the stolen intelligence to blackmail it for employment.

Attila Nemeth, 26, from Hungary, has pleaded guilty in U.S. District Court to hacking and extortion charges stemming from a bizarre case in which he placed backdoor malware on Marriott computers, exfiltrated sensitive documents, and then threatened Marriott with exposing the information if the company didn't offer him an IT position.

The case puts a whole new spin on the targeted attack; rather than trying to cash in on the intelligence or use it for competitive purposes, the perpetrator used it as leverage. Nemeth's methods were similar to those of advanced persistent threat (APT) attackers: He got a foot in the door of Marriott's computers by targeting some of its employees with spear-phishing emails. Marriott did not publicize details about what happened next, but one or more of the users appear to have fallen for the phony emails and either opened infected documents or a link that silently installed a backdoor on Marriott's systems.

"I also found it interesting that instead of using the data to embarrass or ruin Marriott, he used it to try and land a job. It is something I have not seen a lot of, personally. Even in cases where employees go bad, rarely does the attacker want to link his name with the attack, so they will deface, hack, release, and ruin, but try to hide their identity," says Chris Hadnagy, lead developer of Social-Engineer.Org and a professional Social Engineering Penetration Tester and trainer for Social-Engineer.Com. "This man obviously had different goals, and what he found he must have felt was devastating enough to warrant a well-paying job over the release of that intel."

It all started on Nov. 11, 2010, when Nemeth emailed Marriott's personnel group to tell them he had been able to get inside the hotel chain's computers for months and had stolen proprietary data. He warned that if Marriott did not give him a job maintaining the hotel chain's computers, he would reveal the information he had stolen.

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